/*
	Copyright (c) 2004-2011, The Dojo Foundation All Rights Reserved.
	Available via Academic Free License >= 2.1 OR the modified BSD license.
	see: http://dojotoolkit.org/license for details
*/



dojo.declare(
	"dijit.tree.model",
	null,
{
	// summary:
	//		Contract for any data provider object for the tree.
	// description:
	//		Tree passes in values to the constructor to specify the callbacks.
	//		"item" is typically a dojo.data.Item but it's just a black box so
	//		it could be anything.
	//
	//		This (like `dojo.data.api.Read`) is just documentation, and not meant to be used.

	destroy: function(){
		// summary:
		//		Destroys this object, releasing connections to the store
		// tags:
		//		extension
	},

	// =======================================================================
	// Methods for traversing hierarchy

	getRoot: function(onItem){
		// summary:
		//		Calls onItem with the root item for the tree, possibly a fabricated item.
		//		Throws exception on error.
		// tags:
		//		extension
	},

	mayHaveChildren: function(/*dojo.data.Item*/ item){
		// summary:
		//		Tells if an item has or may have children.  Implementing logic here
		//		avoids showing +/- expando icon for nodes that we know don't have children.
		//		(For efficiency reasons we may not want to check if an element actually
		//		has children until user clicks the expando node)
		// tags:
		//		extension
	},

	getChildren: function(/*dojo.data.Item*/ parentItem, /*function(items)*/ onComplete){
		// summary:
		// 		Calls onComplete() with array of child items of given parent item, all loaded.
		//		Throws exception on error.
		// tags:
		//		extension
	},

	// =======================================================================
	// Inspecting items

	isItem: function(/* anything */ something){
		// summary:
		//		Returns true if *something* is an item and came from this model instance.
		//		Returns false if *something* is a literal, an item from another model instance,
		//		or is any object other than an item.
		// tags:
		//		extension
	},

	fetchItemByIdentity: function(/* object */ keywordArgs){
		// summary:
		//		Given the identity of an item, this method returns the item that has
		//		that identity through the onItem callback.  Conforming implementations
		//		should return null if there is no item with the given identity.
		//		Implementations of fetchItemByIdentity() may sometimes return an item
		//		from a local cache and may sometimes fetch an item from a remote server.
		// tags:
		//		extension
	},

	getIdentity: function(/* item */ item){
		// summary:
		//		Returns identity for an item
		// tags:
		//		extension
	},

	getLabel: function(/*dojo.data.Item*/ item){
		// summary:
		//		Get the label for an item
		// tags:
		//		extension
	},

	// =======================================================================
	// Write interface

	newItem: function(/* dojo.dnd.Item */ args, /*Item*/ parent, /*int?*/ insertIndex){
		// summary:
		//		Creates a new item.   See `dojo.data.api.Write` for details on args.
		// tags:
		//		extension
	},

	pasteItem: function(/*Item*/ childItem, /*Item*/ oldParentItem, /*Item*/ newParentItem, /*Boolean*/ bCopy){
		// summary:
		//		Move or copy an item from one parent item to another.
		//		Used in drag & drop.
		//		If oldParentItem is specified and bCopy is false, childItem is removed from oldParentItem.
		//		If newParentItem is specified, childItem is attached to newParentItem.
		// tags:
		//		extension
	},

	// =======================================================================
	// Callbacks

	onChange: function(/*dojo.data.Item*/ item){
		// summary:
		//		Callback whenever an item has changed, so that Tree
		//		can update the label, icon, etc.   Note that changes
		//		to an item's children or parent(s) will trigger an
		//		onChildrenChange() so you can ignore those changes here.
		// tags:
		//		callback
	},

	onChildrenChange: function(/*dojo.data.Item*/ parent, /*dojo.data.Item[]*/ newChildrenList){
		// summary:
		//		Callback to do notifications about new, updated, or deleted items.
		// tags:
		//		callback
	}
});